Abstract

Invasive infections due to Acinetobacter baumannii are among the leading
nosocomial infections in patients hospitalized in the intensive care unit (ICU). An increase in
multidrug-resistant has been observed in recent years. A hospital-based prospective study was
carried out on 287 laboratory-confirmed Acinetobacter species from various clinical samples
out of which 232 (81%) were found to be Acinetobacter baumannii and other species of
Acinetobacter were 55 (19%). Most of the isolates were obtained from pus samples (30.31%)
followed by Urine (25.43%), ET Tip (14.28%) ET Aspirate (12.19%) blood (4.18%). The
number of Isolates was more in IPD (91.99%) and less in OPD (8.01%). Among IPD
patients, the highest number of isolates were obtained from ICU (52.65%), surgery (21.97%),
and Obstetrics and gynecology (13.63%). Isolates showed the highest resistance towards
cephalosporins Ampicillin (89%) followed by Cefotaxime (87%), Ceftazidime (85%), and
ceftriaxone (84%). Among the carbapenem group, Meropenem was found more resistant in
comparison to Imipenem with a resistance rate of 61% and 56% respectively. Colistin was
found to be the most effective drug. Carbapenem resistance among other species of
Acinetobacter was 172 (61.82%) by the Modified carbapenem inactivation method (mCIM).
Out of 172 carbapenem-resistant isolates screened, 144 (83.72%) gave MHT positive that
confirms the production of carbapenemase by the isolates. A total of 140 (97.23%) out of
144 MHT positive isolates showed the presence of the target gene i.e., blaOXA-23.